As a polychloroprene latex composition, an anionic latex employing resin acid as an emulsifier has been well known. However, an anionic latex employing resin acid has a drawback in chemical and mechanical stability when used as a material for an aqueous adhesive. As a means of improving this point, an anionic latex employing a special sulfonate as an emulsifier has been known, but as the latex is acidic, there are such problems that a pH decrease is significant, and a metal may be eroded (e.g. “Adhesion Technology” vol. 21, No. 4 (2002) Serial Number 65 (p. 17, 2.2.2.2)).
In order to solve such problems, a nonionic polychloroprene latex composition employing a polyvinyl alcohol as an emulsifier/a dispersant has been proposed. However, since such a latex itself has a high viscosity, there are such problems that the coating method is limited, and it is difficult to achieve a high solid content by concentration (JP-A-2000-303043 (Claims 1 and 2, Examples 1 to 6), JP-A-2002-53703 (Claims 1 and 2, Examples 1 to 6)).